Method of and apparatus for securing a matrix shell to a suitable backing



,2 sheets-sheet l T. c. ROBERTS METHOD OF AND APPARATUS FOR SECURING A MATRIX SHELL TO A SUITABLE BACKING Filed Dec. 27, 19.19

Mar. 6, 1923. I

Mar. 6, 1923.

T. C. ROBERTS METHOD OF AND APPARATUS FOR SECURING A MATRIX SHELL TO A SUITABLE BACKING Filed Dec. 27, 1919 2 sheets-sheet 2 Inventor Teoaore (6056)??? Patented Mar. 6, I923.

UNITED'STATTESI THEODORE c. RoBERrrs, F nnrnonr onr, c mmences, assfrenon To, 'ogzyr q vrnin;

ensrnornonn mannraorunrns oomrnmg, onsnrnenron'r; oomvzsomircn I A CORPORATION OF DELAWARE.

c m non F AND iPiARA'rUSFtlRfiECURINGA sHnnn'Tojafsnrranrn' I BACK G ap ne'amn filed December T 0 all 807mm 2'25 may mm Be it known that I, THEODORE 'C. ROBERTS,

a citizen of the United States, residing-at Bridgeport, county of 'Fairfield, State of 5 Connecticut, have invented certain new and usefnl lmprovements in Methods 70f and Apgar'aitus for Securing a Matrix Shell-to a ui'table Backing, of which the "following-- is a full, clear, and exact clescriptio'1 1.-

In the manufacture of commerc al phonograph records as now conducted, the rec ords are obta'inedfrom an impression made" in thermoplastic compositions by c' ")"p15er'- hacked matrix shell. The matrixsh'ell is obtained from the master record to be repro-V duced "by electro=deposition of. metal, usually of copper, and is relativelythin. As a consequence when it is laid on a heated surface it warps and does not lie flat and smooth thereon. Itis'there'fore customary to solder a relatively thickfcopp'er plate to the hack of the matrix she'll whereupon'it is ready for use in any suitable manner. 7

his an object of my inyention to provide a method "and means which Willpermi't the utilization of the thin matrix shell Without the copper plate backing heretofore con sidered essential. In carrying out my invention, I take advantage of the fact that different metals have different coefiicients of expansion. As already indicated the matrin shell is usually of copper'or copper compo sition. I, therefore, employ am'etal, namely, steel, preferably in the form of a slab, hav- 85 ing a coeificient of expansion less'than that of copper, for a purpose that Willpresently appear, and back and vmechanica ly secure the matrix against the steel slab and at the same time insure that the matrix, when the slab is heated, shall lie fiat and smooth thereon notwithstanding the factthat the matrix is not integrallynnited therewith as is the case when it is backed with a copper late.

In order that the invention may he more, fully understood reference should beha'd to the detailed description of these-me in con- 27, 1919-. sea-rm, #41 278.

- Fig. 3 ayertiealsection nja efii fgd' I View of'the -r-im cl arn c scale of the central clamping means, and, Fig-.4 a Similar i sm n 7 1 1 i J The numeral 'lfltdesignates "a steeli's lab {of i i "any suitable "onthne'havin'g" aE'griooYe 11' ota radiusjgreater than thajt'of the matrixlfi.

byinieans era "clamping post or bushing 13- and at its outer rim by men-11sec aclainp} mg rin The bushing has a diskhe'ad' 15 at one end and at the other istlireaded to receive "a nut 16' which is s t into .a

counter-bore in the.slab fand proyided with openings 17 adapted to receive "a suitable Wrench. disk 15' is beye'led net 18 and w L. j

c disk are substantially flush. I 7

he c ampi g ri l" lsa t O t ed itab y seated re s a s at 2 e? i gin h r ns ni oc ampin p'dst' qn; I pr er oir fo' ii e a pl ra ty- 0f sc ews 23. a p rough. the b tt m he 'ab into the ring,th e heads o'fthe' I t in th rsla se s at .1 h ni th' surface thereof, The radial clearance be tween the 1 slab and. ring is'reduce'd to a mini:

two 'when'the ma rix s .1. ipositibn. 9 the b, y ip o i insl h la b Withiw cirre' mfeiientia'lhump 24am-1- the ring in inclin'ed Wall '25 "adapted for abutment thereagai st li it he extent hi h the i sf s Ti l, hat e 'me rz lxf i il 't againstthe' slah'iin a smooth and"flat,con.-

so; L The latter at its center is secured to the slab dition.

tion contracts more than the steel slab and as a consequence is drawn taut and smooth across the face of thesame and hence is undertension. By reasonot the clamping ring being circular the matrix is secured to the slab at an infinite number of diametrically opposite points and the matrix is thus uniformly tensioned overits entire area.

l Vhile l: have described the matrix se- 1 of my invention. 3

curing means in detail, it will be obvious that changes may be made in the form, arrangement and proportion of parts thereof without departing from the spirit and scope by Letters Patent is Y 1; The method of securing a matrix to a slab having a coefiicient of expansion less What I claim as new and desire to secure than that of the matrix, which consists in first securing the center of the matrix. to the slab, then heating the matrix and slab to a temperature above the normal working temr perature of the same, then securing the matrix atspaced points to the slab and finally cooling the two toriormal teniperature.

2. The slalohaving a coefiicient of expansion less than that of the matrix, which consists in first securing the center of the matrix to the slab, then heating the matrix'and slab to a temperature sufficiently above the normal working temperature of the same to cause an appreciable difference in normal length of the two, then securing the outer rim of the matrix to the slab and finally cooling the two to normal temperature, I

3. The method of securing a metal matrix to a metal slab having a coefficient of ex pansion less than that of the matrix, which consists in first securing the matrix at its center to the slab, then heating the two to a temperature above the normal working temperature ofthe same, then securing the outer'rim ofthe matrix to the'slab and finally cooling the two to normal tempera ture.

4. The method of securing a matrix to a means having a coeificient of expansion less than that of the matrix which consists in first'securing the center of the matrix to said means, then heatin the matrix andmeans above normal work ng temperature, then securing the matrix to the means at a pinrality of diametrically opposite points and method of securing a matrix to a,

cess against lateral movement, and a clamping ring in substantially fixed radial relation relatively to said clamping means, said ring having a circumferential claw projecting over the face of the backing-plate and adapted to positively secure .the' outer marginal.

portion of thematrix against lateral movement. a

6. A backing means for a matrix krompris ing a backing-plate having adished recess,

a clamping post having beveled disk head for clampingcooperation with said recess and providing a space between the dished recess and'the beveled disc head for clamping a matrix therein, means for drawing the post into matrix clamping position and adapted to positively clamp the matrix against lateral movement, and matrix clamping means radially spaced from and innon-slidable relation with respect to, theiclamping post and adapted to positively secure the matrix against lateral movement.

7.111 combination, a backing-plate having a beveled recess, a matrix backed against the slab and having its central portion'bent into said recess, a clamping post positively securing said portion in the recess against lateral movement, and Y a, clamping ring mounted on the slab in spaced and substantially fixed radial relationto the recess, the ring havinga, claw projecting over the rim of the matrix and adapted to'positively secure the outer marginal portion of the ma-" trix against lateral movement.

8. A backin meansior a matr x, comprising a backing-plate having a central recess, clamping means co-oprating therewith and adapted topositively secure a portion of the matrix within the recess against lateral movement, and-means adaptedto positively secure the matrix to the plate against lateral movement and in concentric and outwardly spaced relation to the first'mentioned clampv ing means. I

9. In combination, matrix backed against it, means adapted to secure the central portion of the matrix against lateral movement, and other means adapted to secure the outer marginal portion of the matrix againstlateral movement, both of said securing means being dependent upon both friction and resistance to'deiormation. l

10. A backing means for a centrally apertured matrix, comprising a centrally apertured backingplate having a recess'surrounding the aperture, clamping means disposed in the recess and adjustable longia backing-plate, a l

tudinally of the axis of the aperture, and adapted to positively clamp the matrix against lateral movement at its inner marginal portion within the recess, the relative dimensions of the clamping means and the recess being such, that the clamping means lies substantially flush with the matrix, and means adapted to positively clamp the outer marginal portion or" the matrix to the plate against lateral movement.

11. A backing means for a centrally apertured matrix, comprising a backing-plate having a central recess, clamping means disposed in the recess and adapted to positively secure the matrix at its inner marginal portion within the recess against lateral movement, the relative dimensions of the clamping means and the recess being such, that the clamping means lies substantially flush with the vmatrix, and means adapted to positively secure the outer marginal portion of the matrix to the plate against lateral movement. v 12. A backing means for a centrally apertured matrix, comprising a centrally apertured backing-plate having a recess surrounding the aperture, clamping means disposed in the recess and adjustable longitudinally of the axis of the aperture, and adapted to positively secure the matrix at its inner marginal portion Within the recess against lateral movement, and means adapted to positively secure the outer marginal portion of the matrix to the plate against lateral movement. I

13. A backing means for a centrally apertured matrix, comprising a centrally apertured backing-plate having a recess surrounding the' aperture, the recess having beveled side walls, clamping means having a beveled head for clamping co-operation with the walls 0t the recess, and adapted to positively clamp the matrix at its inner marginal portion within the recess against lateral movement, and means adapted to positively clamp the outer marginal portion of the matrix to the plate against lateral movement. 14. In combination, a. backing-plate having a central recess, a matrix backed against it, clamping means co-operating with the recess and adapted to positively clamp a portion of the matrix within the recess against lateral movement, the portion being bent, transversely to the lateral surface of the plate, and means adapted to positively clamp the matrix to the plate at its outer marginal portion and against lateralmovement. j I I 15. In combination, a backing-plate, a matrix backed against it, ,a central clamping means secured to the backing-plate and adapted to secure the matrix plate to the backing-plate substantially centrally, a clampin ring secured to. the backing-plate and havlng an annular jaw adapted to grippingly engage the matrix along its outer marginal portion with substantially line contact, and in inwardly spaced relation to the periphery. I

16. In combination, a backing-plate, a matrix backedagainst it, a central clamping means secured to the backing-plate and adapted to secure the matrix plate to the backing-plate substantially centrally, a clamping ringmounted upon the backingplate having an annular portion adapted to engage the backing-plate, an annular portion engaging and adapted to grip the inatrix along its outer marginal portion, an intermediate annular portion spaced from the backing-plate, and adjustable attachment means adapted to secure thebacking-plate to the matrix, and to engage the ring. with the matrix with variable pressure as the intermediate annular portion is drawn into greater or less proximity to the backinglate. p 17. The method of securing a matrix to a support, which consists in first securing the matrix at spaced points, when in a heated condition, and then allowing the matrix to cool.

18. The method of securing a matrix to a, support, which consists in first securing the matrix along a circumferential line, and then causing it to flatten within said circumferential line through thermal contraction of the matrix relative to the support. 7

In testimony whereof, I aflix my signa ture.

THEODORE C, ROBERTS.

Certificate of Correction.

It is hereby certified that in Letters Patent No. 1,4t4:7,183, granted March 6, 1923, upon the application of Theodore C. Roberts, of Bridgeport, Connecticut, for an improvement in Methods of and Apparatus for Securing a Matrix Shell to a Suitable Backing, errors appear in the printed specification requiring correction as follows: Page 8, line 74;, claim 16, after the Word to insert the Word positively same page and claim, line 75, after the word 9 centrally, and line 80, after the Word portion, insert the Words and against lateral movement; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 17th day of April, A. D., 1923.

[SEAL] KARL FENNING,

Acting Commissioner of Patents. 

